Brush construction



G. E. MENGES Sept. 26, 1967 BRUSH CONSTRUCTION Filed oct. 1e, 1964 Flo. s Flo BYSAMNWML ATTO NE YS United States Patent O 3,343,195 BRUSH CONSTRUCTION George E. Menges, Baltimore, Md., assignor to Pittsburgh Plate Glass Company, Pittsburgh, Pa., a corporation of Pennsylvania Filed Get. 16, 1964, Ser. No, 404,401 12 Claims. (Cl. 15--179) This application relates to brushes having metallic filaments of various cross-sectional thickness and, in particular, this application relates to power-driven brushes having metallic filaments of thick cross-section and metallic filaments of thin cross-section wherein the crosssection of each filament is substantially uniform throughout its length.

Power-driven brushes containing metallic filaments, for example, steel wire, are extremely useful for abrading and deburring purposes. Such brushes are used extensively for cleaning metal in preparation for welding, painting, electroplating and the like. The brushes utilized for such purposes must be sturdy and durable and preferably have a long working life. Prior to the instant invention, such brushes had fill material wherein all the wire filaments were substantially the same diameter.

However, it has now been discovered that brushes which have fill material comprising metallic filaments of various thicknesses are more efiicient and have a longer working life than brushes having filaments of the same cross-section. In the brushes of this invention, the distribution of the various sized filaments is substantially uniform throughout the brush fill.

Although in the past, brush constructions using mixtures consisting of part wire and part fiber filaments have been utilized to achieve abrading and sweeping action in the same brush, it is surprising that brush fill which contains a blend or mixture of wires of different diameters yields a tool which gives improved working characteristics, such as increased abrasion with less wire loss. The advantages achieved from the use of a mixture of wire sizes is realized with either straight wire or crimped wire, or mixtures thereof. Furthermore, the advantages realized from the novel constructions of this invention are realized with various cross-sectional configurations, e.g., wires of circular, rectangular, elliptical, or other crosssection.

Brushes utilizing fill material comprising metallic filaments of various cross-sections appear also to have greater stiffness and better inter-filament support than conventional metallic-fill brushes. Also, the brushing action achieved by the novel brushes of this invention is reproducible.

One method of determining the efficiency of a brush used for abrading purposes is to work the brush against a metal surface for a set period of time and determine the amount of metal removed from the metal surface and compare it with the loss of weight of the brush. It has been found that the brushes using wire fill of mixed diameters remove approximately the same amount of metal in the same period of time but with less loss of weight from the brush as when a standard, substantially uniform wire fill brush is utilized. In many instances, the loss of brush fill from a brush having a mixture of wire sizes in the fill has been about 60 percent less than when a standard substantially uniform fill has been utilized. The loss of Weight from brushes containing a mixed wire fill depends upon the ratio of the diameters and the proportion of each. However, advantages are realized when the fill is comprised of wires of different diameters whenever the quantity ratio corresponds to that set forth below.

For a better understanding of the invention, reference may now be had to the drawings.

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FIGURE 1 is a side view of an end brush having fill material of various diameter metallic filaments.

FIGURE 2 is an end view of the brushing tool of FIGURE 1.

FIGURE 3 is a partial sectional side view of an impregnated rotary brushing tool. l

FIGURE 4 is an end view of the brushing tool of FIGURE 3.

FIGURE 5 is a twisted stern brush containing wire filaments of various diameters.

FIGURE 6 is an end view of a brushing tool of FIG- URE 5.

FIGURE 7 represents a brush strip having brush fill of various diameters.

FIGURE 8 is a cup brush having metallic filaments of various diameters.

FIGURE 9 is a rotary brush of twisted tuft construction.

FIGURE 1 is an end brush of the general type described in U.S. Patent 3,007,188, although having fill material of the type described herein. These brushes are well adapted for brushing or buffing of surfaces having cavities and depressions which are difiicult of access by conventional power-driven brushes of the disk or wheel type. The end brush of FIGURE 1 has a casing 3 which has secured therein wire filaments of a thick cross-section 1, wire filaments of an intermediate cross-section 2', and wire filaments of a thinner cross-section 2.

FIGURE 2 is an end view of the brushing tool of FIGURE 1 showing wire filaments of thick cross-section l1 and wire filaments of a thinner cross-section 2.

FIGURE 3 is a partial sectional view of an impregnated brush of the wheel type. The wheel has a plastic layer 4 on the surface and diffused between the wire filaments of the brush. FIGURE 4 is an end view of such a brush showing the plastic interspersed between the thick metallic filaments 1 and the thinner metallic filaments 2.

FIGURE 5 shows a brush having a twisted stem 5 and brush fill comprising metallic filaments of thick cross-section 11 and of thinner cross-section 2.

FIGURE 6 is an end view of the brushing tool of FIGURE 5.

FIGURE 7 depicts a brush strip which is utilized in the construction of brushes of the wheel or cylinder type wherein such a strip is wrapped about an appropriate core to form a brush. FIGURE 7 depicts a brush strip having wire filaments of thick cross-section 1 and of thinner cross-section 2 doubled about a core 7 which retains the filaments within a channel backing 6.

FIGURE 8 depicts a cup brush of the type described in U.S. Patent 3,105,261. FIGURE 8 is a cross-sectional view of such a brush showing the cover plate 8 and the inner plate 9 holding the knots of metallic filaments 10 in position. The wire filaments of this brush are of thick cross-section 1 and of thinner cross-section 2.

FIGURE 9 depicts a rotary brush having fill 13 of twisted tufts of thick filaments 1 and thinner filaments 2 attached to an inner plate 11 which may be anchored to the face plates or outer plates 12 by rivets, bolts, welds or similar means.

As stated above, brushes constructed in the 4manner of this invention with metallic filaments of two or more `diameters are more efficient and more durable than brushes which have fill material composed of filaments of substantially uniform diameter. To achieve the improvement of this invention, it is necessary to use wire laments of two different diameters although wire filaments of three or more different diameters may be utilized, if desired. Filaments which may be successfully utilized in combination range yfrom a diameter ratio of about 1.1 to 1 to about 10 to 1, i.e., the thick filaments may be from about 10 percent to about 100() percent greater thicker filaments may range from a ratio of about 10 to 1 to about 1 to 50 although it is preferred to utilize a ratio of thick filaments to thin filaments of about 5 to 1 to about 1 to 20, although the best results have been obtained from brushes having proportions of thick filaments to thin filaments of about 2:1 to about 1:15. The metallic filaments utilized in this invention may range in diameter from 0.003 inch to about 0.050 inch, although laments having a diameter of about 0.01 inch to about 0.035 inch are preferred. In brushes constructed of commercially available metallic filaments, the filaments of thin crosssection have a minimum diameter of about 0.01 inch to about 0.02 inch and the filaments of thick cross-section have a diameter of about percent to about 100 percent greater than the filaments of thin cross-section.

The -following table indicates typical brush construction of thin and thick filaments.

TABLE A Strand Ratio Strand Ratio Diameter Type of Range Filament Brush The novel brushes of this invention are not limited to brushes having only two different thicknesses of filaments, but include brushes wherein three or more different size filaments are utilized. For commercial purposes, it is not practical to utilize more than three different sizes of filaments in the same brush. In brushes having metallic filaments of thick cross-section, intermediate cross-section, and thin cross-section, it is preferred that each size of filament be present as about 10 percent to about 80 percent of the total metallic filaments present. Also, it is preferred that-the thick filaments be about 10 percent to about 25 percent greater in diameter than the intermediate filaments, and that the intermediate filaments be about 10 percent to about 25 percent greater in diameter than the thin filaments; the thin filaments preferably having a minimum diameter of about 0.010 inch to about 0.020 inch. These figures represent preferred embodiments, and slight deviations therefrom do not substantially affect the unique utility of these brushes.

Metallic filaments useful in this invention may be of the type conventionally utilized in power-driven brushes. Such metallic filaments include hard steel wire, berylhum-.copper wire, stainless steel wire, nickel wire and the like.

If desired, the metallic filamentsv may be embedded in a plastic matrix to maintain the filaments in a set spatial relationto one another. These plastic impregnated brushes are quite useful in many applications. The plastic utilized may be a rubber, neoprene, butadiene-acrylonitrile copolymers, nylon, vinyl polymers and copolymers, melamine resins, unsaturated and saturated polyester resins, polyurethane resins and the like. The plastic matrix should be somewhat resilient and should be resistant to the operating temperatures of the brushing tool.

The thermoplastic material such as the vinyl polymers and copolymers are introduced between the brush filaments by heating the plastic and allowing it to fiow between the filaments. The thermosetting plastics, such as the unsaturated polyester resins, can be reacted in place by introducing the reactive components into a mold containing the brush along with appropriate catalysts, initiators, and the like and causing the reaction to occur, thereby bonding the filaments together.

If desired, fillers such as crushed stone, asbestos powder, clays such as bentonite and Akaolin and the like may be included in the plastic impregnated brushes. The fillers affect the physical characterisitcs of the plastic and enable the plastic to crumble and wear away, thereby continually exposing brush filaments.

Furthermore, if desired, an abrasive may be included in the impregnated brushes. Such abrasives include aluminum oxide, silicon carbide, chrome oxide, pumice, emery, and the like. The inclusion of such an abrasive tends to improve the cutting ability of the brushing tool.

While the embodiments of the invention have been set forth specifically hereinabove, it is not intended to limit the invention solely thereto, butto include all of the variations and modifications falling within the scope of the appended claims.

I claim:

1. A power-driven brush comprising metallic filaments of thick cross-section and metallic filaments of thin crosssection, the proportion of thick filaments to thin filaments being about 10:1 to about 1:50, wherein the filaments of thin cross-section have a minimum diameter of about 0.003 inch and the filaments of thick cross-section have a maximum diameter of about 0.05 inch.

2. A power-driven brush comprising metallic filaments of thick cross-section and metallic filaments of thin cross-section, the proportion of thick filaments to thin filaments being about 5:1 to about 1:20, wherein the filaments of thin cross-section have a minimum diameter of about 0.01 inch and the filaments of thick cross-section have a maximum diameter of about 0.035 inch.

3. A power-driven brush comprising metallic filaments of thick cross-section and metallic filaments of thin crosssection, the proportion of thick filaments to thin filaments being about 2:1 to about 1:15, wherein the `filaments of thin cross-section have a minimum diameter of about 0.01 inch to about 0.02 inch and the filaments of thick crosssection have a diameter of about 10 percent to about 100 percent greater than the filaments of thin cross-section.

4. A power-driven brush comprising metallic filaments of thick cross-section and metallic filaments of thin crosssection, the proportion of thick filaments to thin filaments being about 1:1 to about 1:8, said thick filaments having a cross-sectional diameter of about 0.0115 inch to about 0.0120 inch and said thin filaments having a cross-sectional diameter of about 0.0100 inch to about 0.0110 inch.

5. A power-driven brush comprising metallic filaments of thick cross-section and metallic filaments of thin crosssection, the proportion of thick filaments to thin filaments being about 1:1 to about 1:8, said thick filaments having a cross-sectional diameter of about 0.0130 inch to about 0.0150 inch and said thin filaments having a cross-sectional diameter of about 0.0115 inch to about 0.0125 inch.

6. A power-driven brush comprising metallic laments of thick cross-section and metallic filaments of thin crosssection, the proportion of thick filaments to thin filaments being about 1:1 to about 1:8, said thick filaments having a cross-sectional diameter of `about 0.0150 inch to about 0.0170 inch and said thin filaments having a cross-sectional diameter of about 0.0135 inch to about 0.0145 inch.

7. A power-driven brush comprising metallic filaments of thick cross-section and metallic filaments of thin crosssection, the proportion of thick filaments to thin filaments being about 1:1 to about 1:10, said thick filaments having a cross-sectional diameter of about 0.018 inch to about 0.022 inch and said thin filaments having a cross-sectional diameter of about 0.015 inch to about 0.017 inch.

8. A power-driven brush comprising metallic filaments of thick cross-section and metallic filaments of thin crosssection, the proportion of thick filaments to thin filaments being about 1:1 to about 1:15, said thick filaments hav ing a cross-sectional diameter of about 0.023 inch to about 0.030 inch and said thin filaments having a cross-sectional diameter of about 0.018 inch to about 0.022 inch.

9. A power-driven brush comprising metallic filaments of thick cross-section, metallic laments of intermediate crosssection, and metallic filaments of thin cross-section, each type of filament Ibeing present as about 10 percent to about 80 percent of the total metallic laments present in the brush, said thick filaments being about 10 percent to about 25 percent greater in diameter than said intermediate lilaments and said intermediate filaments being about 10 percent to about 25 percent greater in diameter than said thin filaments, and said thin filaments having a minimum diameter of about 0.010 inch to about 0.020 inch.

10. The power-driven brush of claim 1 wherein said filaments are of various degrees of hardness.

11. The power-driven brush of claim 1 wherein said filaments are substantially maintained in spatial relation to each other by a plastic matrix.

12. The power-driven brush of claim 1 wherein said filaments are crimped.

References Cited UNITED STATES PATENTS FOREIGN PATENTS France. Great Britain.

15 CHARLES A. WILLMUTH, Primary Examiner.

PETER FELDMAN, Assistant Examiner. 

1. A POWER-DRIVEN BRUSH COMPRISING METALLIC FILAMENTS OF THICK CROSS-SECTION AND METALLIC FILAMENTS OF THIN CROSSSECTION, THER PROPORTION OF THICK FILAMENTS TO THIN FILAMENTS BEING ABOUT 10:1 TO ABOUT 1:50, WHEREIN THE FILAMENTS OF THIN CROS-SECTION HAVE A MINIMUM DIAMETER OF ABOUT 0.003 INCH AND THE FILAMENTS OF THICK CROSS-SECTION HAVE A MAXIMUM DIAMETER OF ABOUT 0.05 INCH. 